BM 1609929A20 3/03 3/12/03 10:35 AM Page 10
Grinding Operations
ELECTING GRINDING WHEELS
Before using a grinding wheel, be certain that its maximum safe operating speed is not exceeded by the nameplate speed of the grinder. Do not exceed the recommended wheel diameter.
DISC GRINDING WHEELS
Grinding wheels should be carefully selected in order to use the grinder most efficiently. Wheels vary in type of abrasive, bond, hardness, grit size and structure. The correct type of wheel to use is determined by the job. Use disc grinding wheels for fast grinding of structural steel, heavy weld beads, steel casting, stainless steel and other ferrous metals.
GRINDING TIPS
Efficient grinding is achieved by controlling the pressure and keeping the angle between wheel and workpiece at 10° to 15°. If the wheel is flat, the tool is difficult to control. If the angle is too steep, the pressure is concentrated on a small area causing burning to the work surface.
!WARNING Excessive or sudden pressure on the wheel will
slow grinding action and put dangerous stresses on the wheel.
When grinding with a new wheel be certain to grind while pulling tool backwards until wheel becomes rounded on its edge. New wheels have sharp corners which tend to “bite” or cut into workpiece when pushing forward.
Wire Brush Operations
Wire brushes are intended to “clean” structural steel, castings, sheet metal, stone and concrete. They are used to remove rust, scale and paint.
!WARNING Avoid bouncing and snag- ging the wire brush, espe-
cially when working corners, sharp edges etc. This can cause loss of control and kickback.
